The point of no return for global warming is actually estimated to be 2030. It could be sooner or later. Nobody said the world is going to end in 2030. Anyone who thinks that is an idiot.
Zero population growth was definitely a big deal in the 1960's -- the population bomb was going to lead to mass starvation. The green revolution prevented that. This was before enviro extremists co-opted the word green. The green revolution was the use of new methods; high yield hybrids, chemicals, improved irrigation, and so on, in agriculture, to dramatically boost food production.
Anyway, boomers had been taught to only have 2 children per family to help reduce population growth..
Sort of related; we were also taught to only buy white toilet paper. Does anyone remember the pastel colored TP? You could choose pink, light blue, yellow, lilac, etc. to match your bathroom decor. Apparently the dye was bad for the water supply or something?